Today, age is the most important determinant of woman's ability to conceive both naturally and with treatments such as IVF, but might it be possible to overcome the "biologic clock"?
It is has been understood for many years that a woman is born with all the eggs she will ever produce and that she begins to lose eggs even before she is born. The eggs seem to work reasonably well into the early 30's but in the late 30's and particularly in the 40's the number and quality of those eggs diminish considerably. We know that most if not all of that drop is the result of abnormal chromosomes in the eggs and when genetically abnormal eggs fertilize they produce genetically abnormal embryos. Most genetically abnormal embryos will not implant in the womb, and if they do, they usually miscarry.
These abnormal eggs result from errors in a process call meiosis. If this sounds familiar from high school biology, it is. Meiosis is the process by which reproductive stem cells produce eggs and sperm for reproduction. Most scientists nowadays believe that these errors result, at least in part, from a lack of the energy needed to divide the chromosomes properly, and that energy comes from cell's natural batteries, the mitochondria.
Now, a biotech company has come up with a technique to transfer fresh young, energy-rich mitochondria into a woman's eggs, and has even achieved a live birth with it. Sounds like a miracle cure? Maybe, maybe not. If proven successful and safe, it has the potential to revolutionize IVF treatment for women over 35 and extend the age at which non-donor IVF may be successful. Still, don't expect to see it an IVF clinic near you any time soon. First, we do not know how effective this technique really is and most importantly whether it results in healthy children. The technology involves cloning technology and "3-parent IVF," and it is unlikely that will get past regulatory agencies here in the US anytime soon.